Image display apparatus comprising an internally reflecting ocular optical system

An image display apparatus comprising an image display device for displaying an image, and an ocular optical system for projecting the image formed by said image display device and for leading the projected image to an observer's eyeball,

• said ocular optical system being arranged such that light rays emitted from said image display device are reflected three times before reaching said observer's eyeball, and that a surface of said ocular optical system that is disposed immediately in front of said observer's eyeball is a refracting surface which internally reflects the light rays, and through which the light rays exit from said ocular optical system.

An image display apparatus comprising an image display device for displaying an image, and an ocular optical system for projecting the image formed by said image display device and for leading the projected image to an observer's eyeball,

• said ocular optical system having at least three surfaces, wherein a space formed by said at least three surfaces is filled with a medium having a refractive index larger than 1,
• said at least three surfaces including, in an order in which light rays pass in backward ray tracing from said observer's eyeball to said image display device, a first surface which functions as both a refracting surface and an internally reflecting surface, a second surface which is a reflecting surface facing said first surface and decentered or tilted with respect to an observer's visual axis, and a third surface which is a refracting surface closest to said image display device, so that reflection takes place three times in a path from said observer's eyeball to said image display device.

An image display apparatus comprising an image display device for displaying an image, and an ocular optical system for projecting the image formed by said image display device and for leading the projected image to an observer's eyeball,

• said ocular optical system having at least four surfaces, wherein a space formed by said at least four surfaces is filled with a medium having a refractive index larger than 1,
• said at least four surfaces including, in an order in which light rays pass in backward ray tracing from said observer's eyeball to said image display device, a first surface which functions as both a refracting surface and an internally reflecting surface, a second surface which is a reflecting surface facing said first surface and decentered or tilted with respect to an observer's visual axis, a third surface which is a reflecting surface facing said first surface and adjacent to said second surface, and a fourth surface which is a refracting surface closest to said image display device, so that reflection takes place three times in a path from said observer's eyeball to said image display device.